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<div class="titlepage"><div><div><h3 class="title">
<a name="asio.reference.const_buffer"></a><a class="link" href="const_buffer.html" title="const_buffer">const_buffer</a>
</h3></div></div></div>
<p>
        Holds a buffer that cannot be modified.
      </p>
<pre class="programlisting">class const_buffer
</pre>
<h5>
<a name="asio.reference.const_buffer.h0"></a>
        <span><a name="asio.reference.const_buffer.member_functions"></a></span><a class="link" href="const_buffer.html#asio.reference.const_buffer.member_functions">Member
        Functions</a>
      </h5>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Name
                </p>
              </th>
<th>
                <p>
                  Description
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="const_buffer/const_buffer.html" title="const_buffer::const_buffer"><span class="bold"><strong>const_buffer</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Construct an empty buffer. <br> <span class="silver"> &#8212;</span><br> Construct a buffer to
                  represent a given memory range. <br> <span class="silver"> &#8212;</span><br> Construct a non-modifiable
                  buffer from a modifiable one.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="const_buffer/data.html" title="const_buffer::data"><span class="bold"><strong>data</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Get a pointer to the beginning of the memory range.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="const_buffer/operator_plus__eq_.html" title="const_buffer::operator+="><span class="bold"><strong>operator+=</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Move the start of the buffer by the specified number of bytes.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="const_buffer/size.html" title="const_buffer::size"><span class="bold"><strong>size</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Get the size of the memory range.
                </p>
              </td>
</tr>
</tbody>
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<h5>
<a name="asio.reference.const_buffer.h1"></a>
        <span><a name="asio.reference.const_buffer.related_functions"></a></span><a class="link" href="const_buffer.html#asio.reference.const_buffer.related_functions">Related
        Functions</a>
      </h5>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Name
                </p>
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<th>
                <p>
                  Description
                </p>
              </th>
</tr></thead>
<tbody><tr>
<td>
                <p>
                  <a class="link" href="const_buffer/operator_plus_.html" title="const_buffer::operator+"><span class="bold"><strong>operator+</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Create a new non-modifiable buffer that is offset from the start
                  of another.
                </p>
              </td>
</tr></tbody>
</table></div>
<p>
        The <a class="link" href="const_buffer.html" title="const_buffer"><code class="computeroutput">const_buffer</code></a>
        class provides a safe representation of a buffer that cannot be modified.
        It does not own the underlying data, and so is cheap to copy or assign.
      </p>
<h5>
<a name="asio.reference.const_buffer.h2"></a>
        <span><a name="asio.reference.const_buffer.accessing_buffer_contents"></a></span><a class="link" href="const_buffer.html#asio.reference.const_buffer.accessing_buffer_contents">Accessing
        Buffer Contents</a>
      </h5>
<p>
        The contents of a buffer may be accessed using the <code class="computeroutput">data()</code> and
        <code class="computeroutput">size()</code> member functions:
      </p>
<pre class="programlisting">asio::const_buffer b1 = ...;
std::size_t s1 = b1.size();
const unsigned char* p1 = static_cast&lt;const unsigned char*&gt;(b1.data());
</pre>
<p>
        The <code class="computeroutput">data()</code> member function permits violations of type safety,
        so uses of it in application code should be carefully considered.
      </p>
<h5>
<a name="asio.reference.const_buffer.h3"></a>
        <span><a name="asio.reference.const_buffer.requirements"></a></span><a class="link" href="const_buffer.html#asio.reference.const_buffer.requirements">Requirements</a>
      </h5>
<p>
        <span class="emphasis"><em>Header: </em></span><code class="literal">asio/buffer.hpp</code>
      </p>
<p>
        <span class="emphasis"><em>Convenience header: </em></span><code class="literal">asio.hpp</code>
      </p>
</div>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2018 Christopher M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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